Interrelations of endocrine, pubertal development, and physical growth variables and adolescent adjustment are investigated. Participants are 9-\to 14-year-old boys and girls and their parents. The adolescents and their parents are seen three times, six months apart. Biological measures include plasma hormone level (gonadotropins, sex steroids, and adrenal androgens), stage of pubertal development (Tanner criterion), and height and weight. Psychological measures include assessment of psychological adjustment and behavior problems, cognitive functioning, competence, and self-esteem. Cross-sectional analyses (based on data from the first time of measurement) examining relations among biological measures show sex steroids to be the strongest hormonal correlates of pubertal development and physical growth in boys and adrenal androgens to be the strongest hormonal correlates of pubertal development and physical growth in girls. Cross-sectional analyses of biological and psychological measures revealed more biological correlates of adolescent adjusment and behavior problems for boys than for girls. They also revealed that asynchrony between developmental indices had implications for adjustment and behavior problems. Longitudinal analyses will examine stability and change in adolescent adjustment and behavior in relation to changes in pubertal and endocrine status.